Military commanders are schooled against splitting their forces into smaller groups. Such a tactic rarely provides the advantage that they seem to believe they might achieve. So, why then did GEN Lee not only split off 1/3 (Ewell’s Corps) of his army but then spilt that a second time by sending MG Early’s Division towards York while Ewell’s other two divisions struck out for Carlisle and Harrisburg?
It’s quite simple. Early’s task was to provide a blocking / screening force at York. He was to keep Union reinforcements from arriving at Harrisburg, particularly by rail. He was also supposed to seize (not destroy) a second vital bridge across the Susquehanna River in the vicinity of Wrightsville.
[see Section 22a for a broader discussion of these events near York and Wrightsville.]
A major question can be posed as to why Lee had left Early ‘hanging out to dry’ so far afield from the rest of his army. A companion thought is why Lee thought that Ewell needed two full divisions to attack Harrisburg.
Would it not have been more prudent to have had Rodes’ division occupy Gettysburg in Early’s wake? Such a placement would have protected the Gettysburg-Dillsburg-Carlisle corridor. It would also have precluded Buford’s ambush plan from even being considered. Seemingly, Buford would simply have been repulsed in his 30 June approach and returned to Emmittsburg to report that he had indeed fixed the location of Lee’s Army.
The simple failure to ‘secure’ Gettysburg in that latter days of June, seemingly doomed Lee’s entire northerly invasion plan.